PROJECT SUMMARY/ABSTRACT South Africa remains one of the countries mostly heavily impacted by the HIV epidemic, with an overall estimated adult HIV prevalence of 18% to 30% among female antenatal clinic attendees. There is now substantial evidence that more than 80% of new infections occur within primary male-female partnerships. The high rates of new infections among primary partnerships are attributed to a combination of low levels of HIV testing and a high prevalence of outside sex partners. Recent work by Darbes (MPI), in KwaZulu-Natal (KZN) ? the site of the proposed new research ? found that among a sample of 330 heterosexual couples, 49% of men and 41% of women had no previous HIV testing history. In 20% of couples, neither partner had ever tested for HIV, despite living in a region with one of the highest adult HIV prevalence globally. Beyond the low levels of HIV testing, recent work also demonstrates significant deficits across the continuum of care in South Africa: recent work by Haber in KZN shows that only 45% of HIV-positive individuals are linked to care, 35% initiate ART, and 33% reach viral suppression. There is increasing evidence of efficacy for couples' focused HIV prevention interventions. Couples HIV Testing and Counseling (CHTC) is a proven strategy to reduce the risk of HIV transmission between partners. However, CHTC focuses only on the first stage of the cascade of HIV care ? testing ? are there are no interventions that allow couples to pass through the cascade of care together. Using a randomized controlled trial design with 272 couples, we aim to address this gap in HIV prevention and care literature by comparing a package of dyadic focused HIV testing and counseling interventions, against an attention matched control. The proposed RCT will test the efficacy of the dyadic intervention for achieving gains in viral suppression and engagement in HIV care. Heterosexual couples represent a significant yet over- looked risk group in South Africa, and innovative solutions are urgently needed to improve progression across the continuum of HIV care.